1. Field of the Invention
The present invention generally relates to automobile control pedals, such as brake, clutch and accelerator pedals. More specifically, this invention relates to an adjustable automobile control pedal system whose pedals can be selectively adjusted to allow optimal positioning of the pedals relative to the driver of the automobile.
2. Description of the Prior Art
Automobiles are conventionally provided with foot-operated control pedals, such as an accelerator, brake and clutch pedal, which are used to control the motion and speed of the automobile. Typically, these control pedals are permanently fixed to the vehicle chassis and rotate away from the driver when foot pressure is applied, and are not adjustable relative to the driver or their respective attachment points. Consequently, the control pedals must generally be attached so as to be positioned relative to the floor of the passenger compartment to afford operation which is adequately comfortable for the "average" driver. However, some adjustment of the driver relative to the control pedals is clearly desirable.
Though the driver's seat is usually mounted so as to be slidable in a fore and aft direction to accommodate drivers of different physiques, such an arrangement is only partially effective in positioning the driver relative to the control pedals. Seat adjustment allows the driver to position himself or herself relative to the automobile's steering wheel and the control pedals, to some degree improving the driver's comfort and facilitating the driver's ability to operate the vehicle's primary controls. However, it is nearly impossible for such a solution to accommodate all possible variations in the human frame. In particular, proportional differences between the lengths of a driver's arms, legs and feet in relation to the driver's overall physique cannot be readily accommodated by merely adjusting the seat fore and aft with respect to the control pedals. Accordingly, it has been recognized that some form of control pedal adjustment is desirable to provide optimal comfort to the driver while also ensuring that the driver can fully operate the control pedals at all times.
Many approaches to providing adjustable control pedals have been suggested in the prior art. One approach is to provide some form of ratchet device which allows the entire control pedal assembly to rotation about a primary pivot point. This approach rotates a frame to which the control pedals are each rotatably attached, thus providing rotation of the control pedals in unison relative to the driver. Examples of this approach are illustrated in U.S. Pat. Nos. 3,282,125 to Dully; U.S. Pat. No. 3,400,607 to Smith; and U.S. Pat. No. 3,563,111 Zeigler. A similar approach is to mount one or more control pedals to a frame which is slidable fore and aft as a unit relative to the driver, as illustrated in U.S. Pat No. 2,860,720 to Huff et al and U.S. Pat. No. 4,683,977 to Salmon, and British Patent No. 952,831 to Mussell. Yet another suggested approach is a variation on the two previously mentioned, employing a screw-actuated device to displace a frame to which one or more control pedals are rotatably mounted. The screw-actuated device can be used to either rotate the entire frame about a pivot point, as shown in U.S. Pat. No. 3,151,499 to Roe, or the screw-actuated device can displace the frame fore and aft, as illustrated by U.S. Pat. No. 3,301,088 to White; U.S. Pat. No. 3,643,525 to Gibas; U.S. Pat. No. 3,765,264 to Bruhn, Jr.; U.S. Pat. No. 4,870,871 to Ivan; U.S. Pat. No. 4,875,385 to Sitrin; and U.S. Pat. No. 4,989,474 to Cicotte et al. Typically, the screw-actuated device is disclosed to be driven by an eccentric motor which allows the control pedals to be selectively adjusted by the driver from an appropriate control switch mounted on the dashboard of the vehicle within the driver's reach.
As can be readily appreciated by those skilled in the art, the above examples all require substantial hardware and space beneath the automobile's instrument panel to accommodate the device providing the adjustment feature. Much of the necessary additional hardware can be attributed to the need to avoid effecting the operation of the brake and/or clutch pedals, during adjustment, with their respective hydraulic cylinders. Specifically, the approach chosen must avoid causing the pushrods which actuate the respective cylinder pistons to be displaced relative to their cylinders so as to ensure non-engagement of the brakes and/or the clutch.
In addition, it is generally preferable that the approach chosen have no affect on the mechanical advantage of the control pedal as determined by the control pedal's orientation relative to the pushrod. Generally, the mechanical advantage of a control pedal can be described as the relative effort required to apply the control pedal as compared to the actual force required to actuate the device controlled by the control pedal. For instance, mechanical advantage can be improved by moving the contact point between the control pedal and the cylinder's pushrod toward the pivot point of the control pedal.
To avoid changing the mechanical advantage, the adjustable control pedal assemblies of the prior art generally teach a device in which the control pedals are independently adjusted so as to produce an adverse effect with respect to repositioning of the pedal pivot point relative to the pushrods of the respective operating cylinders, as can be seen with the teachings of Cicotte et al. Alternatively, the adjustment device must be provided with a mechanism which simultaneously adjusts the length of the pushrod to accommodate the displacement of the control pedal assembly, as seen with the teachings of Bruhn, Jr.
Though regarding an unrelated and non-analogous problem associated with optimizing the mechanical advantage of a control pedal, U.S. Pat. No. 3,798,995 to Schroter teaches the use of a variable-ratio control pedal utilizing a camming contour for amplifying the mechanical advantage of the control pedal in the latter stages of the control pedal stroke. The intent with such a device is to maximize the driver's braking capability without the need for excessive forces applied to the control pedal. However, the teachings of Schroter are directed entirely toward achieving an optimal mechanical advantage and do not provide any adjustment of the control pedals with respect to the driver. Further, Schroter does not teach or suggest a solution to the problem of adjusting the positions of the control pedals, nor does Schroter even recognize the problem to which the above prior art is directed.
From the above discussion, it can be readily appreciated that the prior art does not disclose an automobile control pedal arrangement which can be adjusted to adapt to the particular physiological requirements of a driver, while simultaneously avoiding the requirement of mounting the entire control pedal assembly to a frame which is either pivotable or displaceable relative to the driver. Nor does the prior art teach or suggest an apparatus which entails minimal additional hardware to achieve suitable adjustment of one or more control pedals to the effect that no repositioning of the prior art pivot point locations is required and, therefore, no significant structural changes need be made to a conventional control pedal arrangement.
Accordingly, what is needed is a cost-efficient adjustment device for adjusting one or more automobile control pedals, the adjustment device being capable of spatially adjusting the control pedals without repositioning the pivot attachment of the conventional control pedal arrangement to adapt to the physiological demands of a driver, while simultaneously requiring minimal structural reinforcements and modifications to achieve the desired results.